若向量BA=(2,3),CA=(4,7),则BC=_.

问题描述:

若向量

BA
=(2,3),
CA
=(4,7),则
BC
=______.

∵向量

BA
=(2,3),
CA
=(4,7),
BA
=
CA
-
CB

BC
=
BA
+
AC
=
BA
-
CA
=(2,3)-(4,7)=(-2,-4),
故答案为:(-2,-4).